In situ generation of Cu- and Ag–Sn alloys from metal sulfides for CO 2 reduction

Bimetallic sulfide composites Cu 3 SnS 4 and Ag 3 SnS 4 outperform their monometallic counterparts SnS and Cu 2 S as CO 2 RR catalysts. The higher catalytic activity results from the formation of Cu 3 Sn and Ag 3 Sn alloys, where Ag 3 Sn is less prone to corrosion.